Multiple pipe string two-way anchor-and-seal packer



March 28, 1967 c. c. BROWN 3,311,170

MULTIPLE PTFE STRING TWO'WAY ANCHOR"ANDSEAL PACKER Filed oct. 29, 1964 esneetsheet 1 @/cfa c. Wow/v L INVENTOR.

March 28, 1967 c. c. BROWN MULTIPLE PIPE STRING TWO-WAY ANCHOR-AND-SEALPACKER 6 Sheetsheet Filed Oct. 29, 1964 C/CEO C. BROWN INVENTOR.

ATTORNEY March 28, 1967 c. c. BROWN 3,311,170

SEAL PACKER MULTIPLE PIPE STRING TWO-WAY ANCHOR-AND 6 Sheets-Sheet 5Filed Oct. 29, 1964 UVW yf/ZO Gld/560 C. H/POWN INVENTOR.

TTQf/VEY March 28, 1967 C, C, BROWN 3,311,170

MULTIPLE PIPE STRING TWO-WAY ANCHOR-AND-SEAL PACKER Filed Oct. 29, 19646 Sheets-Sheet 4 C. C. BROWN MULTIPLE PIPE STRING TWO-WAYANCHOR-AND-SEAL PACKER 6 Sheets-Sheet 5 March 28, 1967 Filed oct. 29,1964 March 2s, 1967 C. c. BOWN 3,311,170

MULTIPLE PIPE STRING TWO-WAY ANCHOR-AND-SEAL PACKER Filed Oct. 29, 19646 Sheets-Sheet G A7' TURA/Ey United States auPatent 3,311,170 MULTIPLEPIPE STRING TWO-WAY ANCHOR- AND-SEAL PACKER Cicero C. Brown, Brown OilTools, Inc., R0. Box 19263, Houston, Tex. 77024 Filed Oct. 29, 1964,Ser. No. 407,351 19 Claims. (Cl. 166-120) This invention relates tomultiple string packers and particularly to multiple string packersadapted to anchor and seal off a well pipe against pressuredifferentials whether from above or below the seal. Such packers arecommonly referred to as two-way packers.

More conventional two-way packers normally involve relatively complexapparatus arrangements or various and often undesirable manipulations ofoperating strings in order to set and release the packer. Further, suchmore conventional packers commonly require two separate sets of anchorslips usually arranged to act in opposition to one another, and which,therefore, involve a relatively complicated apparatus which is subjectto numerous difculties, particularly in releasing the packer.

The primary object of the present invention is to provide a multiplestring packer which is adapted to hold pressure both from above andbelow the seal and which is relatively simple in construction andoperable for ysetting and release with a minimum amount of manipulationof an operating string or the like.

A further object is to provide a multiple string twoway anchor-and-sealpacker which is set by hydraulic means and released by mechanical means.

A further object is t-o provide a packer of the type described employinga single set of pipe gripping slips and supporting elements adapted toanchor the packer to hold against pressure differentials from above orbelow the seal and which are readily releasable to permit withdrawal ofthe packer from the well pipe in which it is set.

Other and more specific objects and advantages of this invention willIbecome more readily apparent from the following detailed descriptionwhen read in conjunction with the accompanying drawing which illustratesa useful embodiment in accordance with this invention.

In the drawing:

FIGS. 1, 2, 3 and 4 are similar longitudinal, sectional views of thepacker structure showing the parts thereof at several successive stagesin the operation thereof;

FIG. 5 is a view similar to FIGS. 1 to 4 showing the relation of theparts at full release of the packer;

FIGS. 6, 7 and 8 are cross-sectional views taken generally along lines7-7, 8 8 and 9--9, respectively of FIG. l; FIGS. 9 and l0 are enlargedfragmentary, longitudinal sectional views illustrating differentpositions of the anchor elements during the operation of the packer;

FIGS. l1, 12, 13 and 14 are longitudinal sectional views taken generallyrespectively along lines 11-11, 12-12, 13-13 and 14-14 of FIGS. l to 4,respectively; and

FIG. 15 is a View generally similar to FIG. 14, but showing the relationof the parts at a stage of operation intermediate those illustrated inFIGS. 4 and 5.

Referring to the drawing, the packer in accordance with this inventioncomprises an upper body and a lower body 21, both of generallycylindrical form, mounted in longitudinally spaced relation on a firststring tubular mandrel, designated generally M1, and a second stringtubular mandrel, designated generally M2. Upper body 20 is provided witha pair of parallel bores 22 and 23 extending from end to end thereof,and lower body 21 is -provided with a pair of parallel bores 24 and 2Sregistering, respectively, with bores 22 and 23, bores 22 and 24receiving mandrel M1 and bores 23 and 25 receiving Ffice mandrel M2.Mandrel M1 comprises a two-part member including an upper section 26 anda lower section 27. The upper end of the latter carries a section ofspecialized criss-cross threads 28, described in detail in my U.S. Pat.No. l3,083,767, and comprising right and left-hand thread segments. Thethreaded section is received in a threaded a socket portion 29 formed inthe lower end of upper mandrel section -26 and provided with internalleft-hand threads 29a adapted to mate with the corresponding segments ofthreads 28. Socket 29 is slidably disposed in a counterbore 30 extendingfrom the lower end of bore 22 and defining therein la downwardly facingannular shoulder 31. The exterior of socket portion 29 is provided withan external annular shoulder 32 and a bearing ring 33 is mounted aboutmandrel section 26 lbetween shoulders 31 and 32, whereby to provide forfree rotation of upper mandrel section 26 in bore 22 and counter-bore 30for purposes to be explained subsequently. At its lower end counterbore30 receives a bearing ring 35 adapted to provide an anti-frictionbearing for the lower end of upper mandrel section 26 and is held inplace against the lower end of socket portion 29 by means of a threadedgland ring 36 screwed into the lower end of counterbore 30. An O-ring`seal 37 is disposed about the exterior of socket portion 29 to sealbetween the latter and the wall of counterbore 30 below shoulder 32.Lower mandrel section 27 has a length such as to normally project belowbody 21 and is provided near its lower end with an external shoulder 3Swhich forms `a stop limiting downward movement of lower body 21 on themandrel section. The free ends of both mandrel sections 26 and 27 areprovided with thread means for connecting the mandrel and the packerstructure supported thereon into an operating pipe string 1 which iscommonly referred to as the number one string by which the .packer isrun into the well and which is employed to operate the packer.

The lower end portion of bore 23 in the upper body is reduced indiameter and internally threaded to form the socket 40 which is adaptedto threadedly receive the upper end of mandrel M2. The latter has alength such as to normally project -below body portion 21 and isprovided near its lower end portion with an external shoulder 41 adaptedto be engaged by lower body 21 to limit relative upward movement ofmandrel M2. The latter is :also provided adjacent its lower end with aninternal annular seat 42 to receive a plug of any suitable form, such asthe ball B shown in FIG. 2, for closing-oif the bore of mandrel M2against fluid flow downwardly therethrou-gh. The upper portion of bore23 forms a -socket for slidably receiving a latching sleeve or stinger43 fitted with external packing 44 in order to seasl between the stingerand the wall of bore 23. The socket formed by bore 23 is provided with apair of opposed, inwardly projecting J-lugs 45 which are adapted tocooperate with l -slots 46 formed in the lower end of stinger 43. I-lugs45 `and J-slots 46 form a bayonet-type releasable connection between thestinger yand upper body 20 of the packer. Stinger 43 is adapted to beconnected, .as by means of the crolla/r 47, to a second pipe string 2,commonly referred to as the number two string, which normally isinserted into bore 23 after the packer structure has been lowered intothe well on operating string 1. A snap ring 48 is mounted in theexterior of mandrel M2 at a point la short distance above shoulder 41and normally projects radially into a recess 49 formed in the upper endof bore 25 of the lower body to limit upward movement of the latterrelative to mandrel M2 while -permitting the latter to move upwardlyrelative to body 21 for purposes which will appear subsequently.O-frin-g seals 50 and 51 are positioned in bores 24 and 25, re-

spectively, to provide fluid-tight seals between the bores and themandrels extending therethrough.

A seal-and-anchor assembly, designated generally by the letter A, isslidably mounted about both mandrels between upper and lower bodies 20and 21. Assembly A comp-rises a series of elements which considered insuccession from top to bottom, includes an annular seal element S, anupper slip expander member El, a lower slip expander member E2, a `slipcarrier or cage C connecting the expander members to each other, a setof angularly spaced pipe gripping slips G mounted in cage C andoperatively engaged with both expander members, 'and a pressurefluid-operated packer actuator means H, disposed between lower expandermember E2 and lower body 21. Seal element S, expander members El and E2and lactautor means H are all provided with parallel bores coaxial witheach other yand with bores 22, 23 and 24, 25 in upper and lowe-r bodies2t) and 21, respectively, the several bores being adapted to slidablyreceive mandrels M1 and M2.

Seal element S, which is mounted between upper expander member El andthe lower end -of upper body 20, comprises upper and lower seal .rings52 and 53 constructed of exible resilient material separated by ametallic spacer and support ring 54. A metallic compression ring 55 ismounted between lower seal ring 53 and the upper end of expander E1. Thelatter is secured thereto by a plurality of studs 100 which extendthrough the expander member and screw into 'ring 55. As best seen inFIGS. i6 to 15, inclusive, expander member E1 comprises a cylindricalbody 56, the external diameter lof which is somewhat smaller thancompression ring 55, thereby dening the downwardly facing shoulder 57formed by the lower end of ring 55 surrounding expander body 56. Thelower end of the latter is formed with an annular radially enlargedflange 58 which denes an upwardly facing shoulder 59 about the lower endof expander body 56. Expander body 56 has the parallel bores 60 and 61for receiving mandrels M1 and M2, respectively. Bore 61 is provided nearits lower end with a counterbore 62 defining a downwardly facingshoulder 63 which cooperates with a snap ring 64 mounted in the exteriorof mandrel M2 to project therefrom and arranged to be slidahly receivedin counterbore 62 in abutting engagement with shoulder 63 vfor purposesto be explained hereinafter.

Lower expander member E2 com-prises la cylindrical body 65 terminatingat its upper end in van annular radialily extending flange 66 defining adownwardly facing annular shoulder 67 surrounding the upper portion ofexpander bodyk 65. Slip cage C comprises a tubular shell 68 adaptedtosurround flanges 58 and 66 of upper and lower expander members E1 and E2and is provided at its upper end with an inwardly projecting flange 69defining a downwardly facing annular shoulder 70 adapted to rest onshoulder 59 of the upper expander member. The lower end of shell 68 isinternally threaded to receive a tubula-r collar 71 sunrounding body 65of the lower expander member and forming at its upper end an upwardlyfacing internal shoulder 72 abuttable with shoulder 67 `on lowerexpander member E2.

As best :seen in FIGS. 6 to l5, inclusive, slip cage C is provided withgenerally rectangular windows or openings 73 in which `slips G aremounted for generally radial movement. Slips G, cage C and expanderrmembers El and E2 constitute a form of two-way anchor structureconstructed and arranged, when radially expanded, to anchor the packerstructure to a surrounding well pipe W against pressure differentialswhether from above or below the packer seal, and to be readily releasedby upward pull on the supporting mandrels. Such an anchor constructionis fully described and illustrated in my copending U.S. application Ser.No. 299,982, led Aug, 5, l1963. Slips G are sometimes yherein referredto as twoway slips.

As employed in the present application, the anchor structure includeslongitudinally registering slip-receiving slots 74 and 75 in the opposedportions of expander bodies 56 and 65, respectively. Tshese slots haveinwardly sloping bottom surfaces 74a and 75a, respectively, adapted toslidahly engage the opposite end portions of the 'back faces of slips Gwhich extend across the space between the opposed ends of the expanderbodies and have sloping surfaces 76 and 77, respectively, generallycomplementary to bottom surfaces 74a and 75a. Sloping surfaces 76 and 77merge with a mid-portion 76a on the back faces of the slips. The outerface of each of the slips is formed to provide a lower generallysmooth-surfaced area 78 and an upper portion provided with pipe-engagingteeth 78a which project outwardly with respect to areas 78 so that whenthe toothed portions are in gripping engagement with the wall of wellpipe W, a clearance space will be provided betweenV the smooth-surfacedareas of the slips and t-he surrounding wa-ll of well pipe W (FIG. 9).This space will permit rearward rocking movement of the toothed upperportions of the slips when upper expander El is moved upwardly out ofengagement with sloping back surfaces 76 of the slips and upwardpressure is exerted against the lower ends of the slips. Thelongitudinal margins of the back faces of the slips are provided withlaterally projecting ribs or flanges 79 disposed to prevent outwarddislodgement of the slips from windows 73 while permitting the limitedamount of radial or rocking movement of the slips noted previously andas will be more Ifully described hereinafter.

Fluid pressure actuator H comprises a cylindrical piston 80 slidable onmandrels M1 and M2 and xedly secured to the lower end of lower expandermember E2 by means of the studs 101. The exterior of the piston has adiameter substantially equal to that of lower expander body 65. Collar71 which surrounds lower expander body -65 extends downwardly la shortdistance below the latter to slidably enclose the upper portion ofpiston '80. The lower portion of the latter is enlarged externally toform the piston head l81 and a cylinder sleeve 82 surrounds head 81, thelower end of collar 71 and the upper portion of lower body 21. 'Thelower end of cylinder sleeve 82 is fixedly secured .to lower body 21 andits upper end is initial-ly releasably secured to the :lower end ofcollar 71 Iby means of one or more shear screws 83. A seal ring 84 isdisposed lin the exterior of piston head 81 to form a Aslidable sealbetween the latter and cylinder sleeve 82. Packing rings 85, 86 sealbetween piston head 81 and mandrels M1 and M2, respectively. A packingring -87 forms a seal between the exterior of lower body 21 and cylindersleeve 82. The space between the :lower end of piston head v81 and theupper end of lower -body 21 defines an expanstible pressure chamber '88which is in communication with the ybore of mandrel M2 by means of aplurality of ports 89 extending. through the wall of mandrel M2 atpoints adjacent the lower end of piston head 81. Collar 71 is initiallyreleasably secured to body 65 of lower expander mem-ber E2 by means ofone or more shear screws 91 and the upper end of cage C is likewiseinitially releasalbly secured to body 56 of the upper expander mem-berE1 'by means of one or more shear screws 90. Shear screws 83, and 91 areselected to be of successively greater strength, that is, the combinedbreaking strength of shear screws 83 will be less than that of shearscrews 90, and the latter, in turn, will be of lesser strength thanshear screws 91, these relative strengths 'being required in connectionwith the operation of the device as will appear hereinafter.

As seen in FIGS. 8 and 1l to 15, piston Sil' is connected to lower body21 :by a plurality of parallel cylindrical setting rods 92 which havetheir upper ends screwed into piston head 81 and their lower endsextending through spaced parallel openings 93 in lower body 21. Openings93 are formed to a downwardly tapering conical shape adapted to receivea plurality of small buttress-.toothed wedges 94 surrounding rods 92.Small sealed ring pistons 95 are seated in openings 93 surrounding rods92 on top of f Y wedges 94 and are held in place -by snap rings 96. Withthis arrangement, 4it will be evident that when lluid pressure isintroduced into chamber `88 forcing piston 8) upwardly relative to lowerbody 21, rods 92 will, at the same time, be pulled upwardly throughopenings 93 and wedges 94, lbut the latter under the pressure applied tothe upper ends thereof through the small ring pistons and through thereaction between .the taper of openings 93-and wedges 94 will be causedto grip rods 92 and prevent retractive movement of piston V80 relativeto lower body 21.

Operation of the device iis as follows: The structure shown in FIG. 1and mounted on tubing string 1, will be lowered into well pipe W ito thepoint at which it is -to be set. The second pipe string 2 carryingstinger 43 will be lowered into the well and inserted into bore 23 androtated slightly to the extent required to engage I -slots 46 with J-lugs 45, to thereby securely lock the tubing string 2 into upper body20. In this initial stage of the operation, it will be noted that allsets of shear screws 83, 96 and 91 wil-l Ibe in a position whereby tohold the upper and lower expander members E1 and E2 in their relativelyretracted relation, slips G Ibeing accordingly retracted as best seen inFIG. 11.

A plug, such as ball B, will be dropped or pumped through tubing string2 to engage seat 42 and close the bore of mandrel M2 (FIG. 2).Thereupon, the pressure will Ibe increased on fluid pumped into tubingstring 2 and will enter pressure chamber `88 through ports `89. As lower`body 21 will be held against downward movement on shoulder 38, thepressure will -be exerted against piston 80 and will be increased untilit attains a force necessary to rupture shear screws 83, the weakest inthe several series of screws (FIG. 2). Upon rupture of -shear screws 33,piston 80 will continue upward movement, urging lower expander member E2upwardly which will raise slip cage C and through the connection formedby shear screws 91, will also urge upper expander member Elv upwardly,compressing seal member S and ex- ,panding it into sealing engagementwith the wall of well pipe W. As this compressive force increases, shearscrews 90, being somewhat weaker than shear screws 91, will then rupture(FIG. 3), 4permitting lower expander member E2 to continue its upwardmovement while upper expander member E1 remains stationary. This upwardmovement' of lower expander member E2 will carry slips -G upwardly alongwith slip cage C (FIG. 13), moving the upper inclined portions of theslips over the corresponding inclined surfaces of upper expander memberE1 and moving the slips radially into gripping engagement with the wallof well pipe W. As the slips bite into the wall of well pipe W,continued increasing upward force 'being applied to piston 80, willattain a force sufricient to -break shear screws 91. This will thenpermit lower expander member E2 to move upwardly relative to slip cage C(FIGS. 4 and 14), moving the lower expander member E2 into engagementwith the lower inclined surfaces 77 of the slips, .thereby additionallyurging the latter outwardly into ever tighter .gripping engagement withthe wall of well pipe W.

Also, as piston S0 moves upwardly in performing the above-describedsequence of operations, setting rods 92 will tbe Ipulled upwardlythrough openings '93 and over the toothed faces of wedge slips 94. Whenpiston Si) has Vcompleted its sequence of upward movements, whichresults in compression of seal member S and the setting of slips G, atwhich point the packer will be set, rods 92, through their engagementwith wedge slips 94, will prevent retraction of piston 80, and therebywill hold the packer in the set position which it has attained.

Since upper and lower expander members E1 and E2 are both in fullengagement with slips G and in opposing relation, it will be seen thatthe packer will now be held firmly against pressure differentialsWhether exerted from above or below the packer.

When i-t is desired to release the packer, the following sequence ofsteps is conducted: Tubing string 2 will be released by movementssulicient to disen'gage the I- connection and withdrawn from the Well.Pipe string 1 will then be rotated in the right-hand direction. Thiswill cause upper section 26 of mandrel M1 to rotate in counterbore 3)and by reason of the engagement of lefthand threads 29a with theleft-hand thread segments of criss-cross threads 28, lower mandrelsection 27 will be caused to move downwardly, since the upper mandrelsection `cannot move upwardly, until the upper end of lower mandrelsection 27 has been completely unscrewed from the upper section.Thereupon, an upward pull is applied to tubing string 1 to lift upperbody 2@ of the packer. This will allow seal element S to retract andwill also apply upward pull to upper expander member E1, causing thelatter to move upwardly relative to slips G and providing a clearancespace behind the upper portions of slips G. Continued upward movement ofupper expander member E1 will bring shoulder 59 into engagement withshoulder 7l) of the slip cage, transferring the upward movement to thelatter which will, in turn, move upwardly until the lower end walls ofopenings 73 strike the lower ends of slips G. The upward force thusexerted against the lower ends of the slips will cause the latter torock about a fulcrum formed between the upper ends of inclined surfaces7551 and the adjacent portions of the slips. Because of the clearancebetween the smooth surfaced area 78 of the slips and the surroundingwell wall, the rocking movement will be accommodated by allowing thelower portion of the slips to swing outwardly while the upper portionwill swing inwardly toward inclined surface 74a of the upper expandermember, thereby pulling the slip teeth 78 out of engagement with thewall of pipe W and freeing the slips from engagement with the latter(FIGS. l0 and 15). With the slips thus released and seal element Sretracted, as described, the packer is now free to be withdrawncompletely from the well and this can be done as illustratedparticularly in FIG. 5, from which it will be noted that lower section27 of mandrel M1 remains in the well attached to the tubing string 1 andto any other packers or other equipment mounted thereon and positionedin the well. It will be noted also that when the packer is thus fullyreleased and pulled upwardly, lower ibody 21 will be held againstfalling olf of mandrel M2 by engagement with shoulder 38 (FIG. 5). i

From the foregoing, it will be seen that a multiple pipe string packer,in accordance with this invention, provides a two-way packer which maybe set hydraulically and may be released mechanically by minimum amountof rotation of the operating string, thereby reducing the amount ofmanipulation for setting and releasing the packer -to a minimum.Moreover, by providing in a multiple pipe string packer of the kindillustrated, the arrangement com- 'prising the opposed expander membersin cooperation with the two-way slips, the complexity of the packer isgreatly reduced as compared with more conventional twoway packers, andthe operation thereof is not only greatly simplied but renderedsubstantially trouble-free.

It will be understood that when the packer has been withdrawn from thewell, as described above, a conventional overshot or the like can be runinto the well to be coupled to mandrel M1 by conventional right-handrotation, so that tubing string 1 remaining in the well and its attachedequipment may also be withdrawn, as required. I

The relative strengths of the several shear screws will be selected, aswill be evident to those skilled in the art, to assure the breaking ofthe screws in their proper order and shear screws of various strengthsmay be selected for this purpose, depending on conditions to beanticipated and the nature of the equipment. By way of example, shearscrews 83 may comprise three V16 NC, SAE 4140, shear screws having acombined shear strength of 13,230 pounds. With an effective area of thecylinder 82 of 14.54 sq. in., a pressure of 910 lbs/in.2 would shearthese screws. Shear screws may comprise live 1/2 NC shear screws havinga combined shear strength of 30,000 pounds. These screws would shearupon the lapplication of about 2,060 lbs./in.2. Shear screws 9i maycomprise five NC shear screws having a combined strength of 39,000pounds. These screws would shear upon application 2700 lbs/in.2pressure.

It will be understood that in operation, the increases in presure willoccur rapidly and the breaking of the shear screws will occur insuccession also quite rapidly, so that the setting of the packer willoccur in a very brief period of time once the liuid pressure has begunto be increased.

While the illustrative embodiment shows the packer construction inaccordance with this invention adapted for use with two pipe strings, itwill be understood that the same construction `can be readily adaptedfor use with more than two pipe strings, as will be apparent to thosefamiliar with this art.

It will be understood that various changes and modifications may be madein the details of the illustrative embodiment within the scope of theappended claims but without departing from the spirit of this invention.

What I claim and desi-re to secure by Letters Patent is:

1. A multiple pipe string two-way well packer, including, a packer bodycomprising longitudinally spaced upper and lower body sections havingaxially registering parallel first and second bores extendinglongitudinally therethrough, first and second tubular mandrels havingtheir upper ends secured respectively in the first and second bores ofthe upper body section and extending slidably through the registeringbores in the lower body section, a seal-and-anchor assembly mountedabout both mandrels between said body sections, said assembly includinga resilient seal element disposed in abutting relation to the lower endof said upper body section for radial expansion by end-wise compressionthereagainst, upper and lower longitudinally spaced slip expandermembers disposed beneath said seal element and longitudinally slidableon said mandrels, a slip cage having angularly spaced openings thereindisposed about said expander ,members for limited longitudinal slidingmovement relative thereto, pipe-gripping slips mounted in said openingsfor radial movement therein and having upper and lower end portionsdisposed for wedging engagement respectively with said upper and lowerexpander members whereby axial movement of said expander members towardeach other will urge said slips outwardly into pipegripping position,fiuid pressure-operated actuating means disposed about the mandrelsbetween the lower expander member and said lower body section, means forsupplying pressure fluid from said second mandrel to said actuatingmeans, and a series of separate retainer elements initially holding saidactuating means and said upper and lower expander elements innon-actuating positions, said retainer elements being operable byprogressive pressure increase on said actuating means to sequentiallyrelease said actuating means, said upper expander member and said lowerexpander member for relative longitudinal movement to positionsactuating said seal-and-anchor assembly.

2. A well packer according to claim 1 wherein said first mandrelcomprises coaxial upper and lower sections, said upper mandrel sectionbeing rotatable in said first bore in vsaid `upper body section, andleft-hand thread means connecting said mandrel sections.

3. A well packer according to claim 1 wherein said :actuating meansincludes a piston member longitudinally :slidable on said mandrels, andcooperating means car- -ried by said piston member and said lower bodysection constructed and arranged to permit only upward movement of sa-idpiston member on said mandrels.

4. A multiple pipe string two-way well packer, including, a packer bodycomprising longitudinally spaced upper and lower body sections havingaxially registering parallel first and second bores extendinglongitudinally therethrough, first and second tubular mandrels havingtheir upper ends secured respectively in the first and second bores ofthe upper body section and extending slidably through the registeringbores in the lower body section,

a seal-an-anchor assembly mounted about both mandrels Y between saidbody sections, said assembly including a resilient seal element disposedin abutting relation to the lower end of said upper body section forradial expansion by end-wise compression thereagainst, upper and lowerlongitudinally spaced slip expander members disposed beneath said sealelement and longitudinally slidable on said mandrels, a slip cage havingangularly spaced openings therein disposed about said expander membersfor limited longitudinal sliding movement relative thereto,pipe-gripping slips mounted in said openings for radial movement thereinand having upper and lower end portions disposed in wedging engagementrespectively with said upper and lower expander members whereby axialmovement of said expander members toward each other will urge said slipsoutwardly into pipe-gripping position, fluid pressure-operated actuatingmeans disposed about the mandrels between the lower expander member andsaid lower body section, means for supplying pressure fluid from saidsecond mandrel to said actuating means, and a series of separateretainer elements initially holding said actuating means and said upperand lower expander elements in non-actuating positions, said retainerelements having different holding strengths such as to be operable byprogressive pressure increase on said actuating means to sequentiallyrelease said actuating means, said upper expander member and said lowerexpander member for relative longitudinal movement to positionsactuating said seal-and-anchor assembly.

5. A well packer according to claim 4 wherein said retainer elementscomprise shear screws means.

6. A well packer according to claim 4 wherein said retainer elementscomprise first shear screw means connecting said actuating means to thelower body section, second shear screw means connecting said slip cageto said upper expander member, and third shear screw means connectingsaid slip cage to said lower expander member.

7. A well packer according Ito claim 4 wherein said first mandrelcomprises coaxial upper and lower sections, said upper mandrel sectionbeing rotatable in said first bore in the upper body section, andleft-hand thread means connecting said mandrel sections.

8. A multiple pipe string two-way well packer, including, a packer bodycomprising longitudinally spaced upper and lower body sections havingaxially registering parallel `lirst and second bores extendinglongitudinally therethrough, first and second tubular mandrels havingtheir upper ends secured respectively in the first and second bores ofthe upper section and extending slidably through the registering boresin the lower body section, a sealand-anchor assembly mounted :about bothmandrels between said body sections, said assembly including a resilientseal element disposed in abutting relation to the lower end of saidupper body section for radial expansion by end-wise compressionthereagainst, upper and lower longitudinally'spaced slip expandermembers disposed beneath said seal element and longitudinally slidableon said mandrels, a slip cage having angularly spaced openings thereindisposed about said expander members for limited longitudinal slidingmovement relative thereto, pipe-gripping slips mounted in said openingsfor radial movement therein and having upper and .lower end portionsdisposed in wedging engagement respectively with said upper and lowerexpander members whereby axial movement of said expander members towardeach other will urge said slips outwardly into pipe-gripping position,cooperating means on the slip cage and said slips operable in responseto upward movement of the upper expander member relative to the lowerexpander member to move said slips out of pipe-gripping position, liuidpressure-operated actuating means disposed about the mandrels betweenthe lower expander member and said lower body section, means forsupplying pressure fluid from said second mandrel to said actuatingmeans, and a series of separate retainer elements initially holding saidactuating means and said upper and lower expander elements innon-actuating positions, said retainer elements having diterent holdingstrengths such as to be operable by progressive pressure increase onsaid actuating means to sequentially release said actuating means, saidupper expander member and said lower expander member for relativelongitudinal movement to positions actuating said seal-and-anchorassembly.

9. A well packer according to claim 8 wherein said first mandrelcomprises coaxial upper and lower sections, said upper mandrel sectionbeing rotatable in said rst bore in said upper body section, andleft-hand thread means connecting said mandrel sections.

l10. A well packer according to claim 9 wherein said actuating meansincludes a pistonmember longitudinally slidable on said mandrels, andcooperating means carried by said piston member and said lower bodysection constructed and arranged to permit only upward movement of saidpiston member on said mandrels.

11. A well packer according to claim 10 wherein said reta-incr elementscomprise shear screw means.

12. A well pac-ker according to claim 10 wherein said retainer elementscomprise first shear screw means connecting said piston member to saidlower body section, second shear screw means connecting said slip cageto said upper expander member, and third shear screw means connectingsaid slip cage to said lower expander member.

13. A multiple pipe string two-way well packer, including, a packer bodycomprising longitudinally spaced upper and lower body sections havingaxially registering parallel rst and second bores extendinglongitudinally therethrough, first and second tubular mandrels havingtheir upper ends secured respectively inthe iirst and second bores ofthe upper body section and extending slidably through the registeringbores in the lower body section, a seal-and-anchor assembly mountedabout both mandrels between said body sections, said assembly includinga resilient seal element disposed in abutting relation to the lower endof said upper body section for radial expansion by end-wise compressionthereagainst, upper and lower longitudinally spaced slip expander memberdisposed beneath said seal element and longitudinally slidable on saidmandrels, said expander members having opposed inwardly inclined wedgingsurfaces, a slip cage having angularly spaced openings therein disposedabout said expander members `for limited longitudinal sliding movementrelative thereto, pipe-gripping slips mounted in said openings forradial movement therein and having on their back faces upper and lowerinclined end portions disposed for wedging engagement respectively withsaid wedging surfaces on said upper and lower expander members wherebyaxial movement of said expander members toward each other will urge saidslips outwardly into pipegripping position, the outer faces of saidslips having a lower non-gripping area and an upper pipe-gripping sur-`face projecting outwardly relative to said non-gripping area,cooperating means on the slip cage and said slips operable in responseto upward movement of the upper expander member relative to said lowerexpander member to rock said pipe-gripping surfaces rearwardly out ofpipe-gripping position, duid pressure-operated actuating means disposedabout the mandrels between the lower expander member and said lower bodysection, means for supplying pressure iiuid from said second mandrel tosaid actuating means, and a series of separate retainer elementsinitially holding said actuating means and said upper and lower expanderelements in non-actuating positions, said retainer elements havingdifferent holding strengths such as to be operable by progres-sivepressure increase on said actuating means to sequentially release saidactuating means, said upper expander member and said lower expandermember for relative longitudinal movement to positions actuating saidseal-and-anchor assembly.

14. A well packer according to claim 1.3 wherein said -first mandrelcomprises coaxial upper and lower sections, said upper mandrel sectionbeing rotatable in said first bore in said upper body section, andleft-hand thread means connecting said mandrel sections.

15. A well packer according to claim 14 wherein said actuating meansincludes a piston member longitudinally slidable on said mandrels, andcooperating means carried by said piston member and said lower lbodysection constructed and `arranged to permit only upward movement of saidpiston member in said mandrels.

16. In a well packer according to claim 15, means securing said upperexpander member to said seal element, and means securing said pistonmember to said lower expander member.

17. A well packer according to claim 15 wherein said retainer elementsare shear screw means.

18. A well packer according to claim 15 wherein said retainer elementscomprise first shear screw means connecting said piston member to saidlower body section, secondshear screw means connecting said slip cage tosaid upper expander member, and third shear screw means connecting saidslip cage to said lower expander member.

19. A multiple pipe string two-way well packer, including, a packer bodycomprising longitudinally spaced upper and lower body sections havingaxially registering parallel rst and second bores extendinglongitudinally therethrough, iirst and second tubular mandrels havin-gtheir upper ends -secured respectively in the rst and second bores ofthe upper .body section and extending slidably through the registeringbores in the lower body section, a seal-and-anchor assembly mountedabout both mandrels between said body sections, said assembly includinga resilient seal element disposed in abutting relation to the lower endof said upper body section for radial expansion by end-wise compressionthereagainst, upper and lower longitudinally spaced slip expandermembers disposed beneath said seal element and longitudinally slidableon said mandrels, a slip cage having angularly spaced openings thereindisposed about said expander members for limited longitudinal slidingmovement relative thereto, pipe-gripping slips mounted in said openingsfor radial movement therein and having upper and lower end portionsdisposed Ifor wedging engagement respectively with said upper and .lowerexpander members whereby axial movement of said expander members towardeach other will urge said slips outwardly into pipegripping position,uid pressure-operated actuating means disposed about the mandrelsbetween the lower expander ymember and said lower body section, andmeans for supplying pressure fluid from said second mandrel to saidactuating means.

References Cited by the Examiner UNITED STATES PATENTS Re. 25,846 8/1965Campbell 16d-122 2,121,050 6/1938 Ragan et al. 166-134 3,191,682 6/1965Cochran 16d-L20 3,224,508 lil/1965 Cochran 1616- CHARLES E. OCONNELL,Primary Examiner.

J. A. -IJEPPINK, Assistant Examiner.

19. A MULTIPLE PIPE STRING TWO-WAY WELL PACKER, INCLUDING, A PACKER BODYCOMPRISING LONGITUDINALLY SPACED UPPER AND LOWER BODY SECTIONS HAVINGAXIALLY REGISTERING PARALLEL FIRST AND SECOND BORES EXTENDINGLONGITUDINALLY THERETHROUGH, FIRST AND SECOND TUBULAR MANDRELS HAVINGTHEIR UPPER ENDS SECURED RESPECTIVELY IN THE FIRST AND SECOND BORES OFTHE UPPER BODY SECTION AND EXTENDING SLIDABLY THROUGH THE REGISTERINGBORES IN THE LOWER BODY SECTION, A SEAL-AND-ANCHOR ASSEMBLY MOUNTEDABOUT BOTH MANDRELS BETWEEN SAID BODY SECTIONS, SAID ASSEMBLY INCLUDINGA RESILIENT SEAL ELEENT DISPOSED IN ABUTTING RELATION TO THE LOWER ENDOF SAID UPPER BODY SECTION FOR RADIAL EXPANSION BY END-WISE COMPRESSIONTHEREAGAINST, UPPER AND LOWER LONGITUDINALLY SPACED SLIP EXPANDERMEMBERS DISPOSED BENEATH SAID SEAL ELEMENT AND LONGITUDINALLY SLIDABLEON SAID MANDRELS, A SLIP CAGE HAVING ANGULARLY SPACED OPENINGS THEREINDISPOSED ABOUT SAID EXPANDER MEMBERS FOR LIMITED LONGITUDINAL SLIDINGMOVEMENT RELATIVE THERETO, PIPE-GRIPPING SLIPS MOUNTED IN SAID OPENINGSFOR RADIAL MOVEMENT THEREIN AND HAVING UPPER AND LOWER END PORTIONSDISPOSED FOR WEDGING ENGAGEMENT RESPECTIVELY WITH SAID UPPER AND LOWEREXPANDER MEMBERS WHEREBY AXIAL MOVEMENT OF SAID EXPANDER MEMBERS TOWARDEACH OTHER WILL URGE SAID SLIPS OUTWARDLY INTO PIPEGRIPPING POSITION,FLUID PRESSURE-OPERATED ACTUATING MEANS DISPOSED ABOUT THE MANDRELSBETWEEN THE LOWER EXPANDER MEMBER AND SAID LOWER BODY SECTION, AND MEANSFOR SUPPLYING PRESSURE FLUID FROM SAID SECOND MANDREL TO SAID ACTUATINGMEANS.